Definition of fire-breathing in US English:

fire-breathing

adjective

  • 1(of a mythical creature) capable of exhaling flames.

    ‘the enormous fire-breathing dragon’
    1. 1.1 Denoting a person who takes fuel into their mouth and spits it out over a flame to produce a jet of fire as a form of entertainment.
      ‘they hired fire-breathing entertainers to amuse their guests’
  • 2Characterized by an intensely zealous or aggressive manner of expression.

    ‘a novel with fearless, fire-breathing prose’
    ‘this famously fire-breathing woman turned out to be an amicable companion’